Double lepton pair production with electron capture in relativistic heavy-ion collisions

Abstract

We present a theoretical study of a double leptonpair production in ultra-relativistic collision between two bare ions. Special emphasis is placed to processes in which creation of (at least one) e + e − pair is accompanied by the capture of an electron into a bound ionic state. To evaluate the probability and cross section of these processes we employ two approaches based on (i) the first-order perturbation theory and multipole expansion of Dirac wavefunctions, and (ii) the equivalent photon approximation. With the help of such approaches, detailed calculations are made for the creation of two bound-free e + e − pairs as well as of bound-free e + e − and free-free μ + μ − pairs in collisions of bare lead ions, Pb 82+ . The results of the calculations indicate that observation of the double lepton processes may become feasible at the LHC facility.

Double scattering production of two positron–electron pairs in ultraperipheral heavy-ion collisions

“…The main ALICE detector allows for the particle identification practically down to transverse momenta of 0.2 GeV, which makes it rather special. The number for full rapidity coverage and p t > 0.2 GeV given in the table is much (three orders of magnitude) smaller than the total cross section for two pair production [8], where it was estimated to be about 10 mb. In Fig.4 we show our predictions for the opossite-sign dσ/dy 1 dy 2 (left panel) and the same-sign dσ/dy 1 dy 3 (right panel) electrons.…”

“…1) was discussed e.g. in the context of bound-free production [8]. There rather total cross section is discussed.…”

Ultraperipheral heavy-ion collisions in Run3 - verification of what we know or new physics?

“…without imposing a limitation on kinematic variables, Ref. [40]. Formalism taking into account the integral over the impact parameter allows determining the value of the total cross section and the distribution of the impact parameter.…”